Kaboom question

[Tuckerp229]

With my tail over my eyes I humbly submit this kaboom from my range trip today.  I have been reloading now for about 6 years without mishap. Today I went with my .30 carbine and most recent reloads to test some new bullets from Reminton. My recipe was straight from the Speer manual #13 page 262. I was using 14 grains of IMR 4227 behind Remington's .30 carbine jacketed soft points 110 grain. OAL was 1.66 inches. This recipe has been very good to me using straight lead 110 grain bullets for 2 years. I just decided to make up the jacketed bullets for better accuracy and less fouling.
The first 4 shots were quite impressive...less than 1/2 inch at 25 yards open sights and about 1 inch at 50 yards.  The fifth shot toward the 100 yard range went Kaboom! I was uninjured by the grace of God but my carbine lost some wood out of the stock on the right side all along the action.  No metal shows any sign of fatigue or cracks.  The bullet case remained in the chamber with the entire bottom end blown away. The brass looks much like the typical HP bullet after expansion. Also the mag bottom blew off and all the rounds in the mag were forced out of the mag.  Again no damage to the mag. I just reassembled it.
Other pertinent points: I use a Dillon XL650 with the over/under charge auto alarm. While it is possible...maybe probable that I double/ over charged the case I am  none the less perplexed. The bullets are new to me and this recipe. I used a micrometer to verify the size and they run .303-.304 so seem OK.   The 14 grains is dead in the middle of the Speer min/ max load.
It almost appears that the gun fired without the bolt being fully locked in place.  This a WWII carbine so wear is possible.
Does anyone have any ideas as to the cause or does this seem like an obvious reloader error? I reason for probing the experience of you reloaders is to determine the real cause to avoid a repeat experience wherein I may not be so lucky. 

[cwlongshot]

Well, for one thing there is a big difference between a LEAD bullet load and a JACKETED one. NEVER mix the two. I am gald your OK!!!

 Having said that it appears that your load is within manual specs so what exactly happened may remain a mystery/ You say you have had some good groups just prior. So a obstructed bore is unlikely... Over charge is a def possibility. Did anything else change in your recipe? Like diff primers, cases or powder lot?

CW

[Tuckerp229]

No, the powder and primers were the same.  I hate the idea of a permanent mystery. If it was actually an overcharge it really perplexes me due to the Dillon overcharge alarm. It has never failed me.
I still wonder if the gun fired without the rotary bolt being locked into place. I wonder if a gunsmith can "read the gun" and exploded round? 

[cwlongshot]

That is a definate "maybe". Try it for your self with no bullets of coarse..  ;DSee if you can get it to fire with out the bolt completely closed...

CW

[stimpylu32]

Turkerp229

Glad your ok , could have been much worse . Sounds like one of three things happened here .

1)  a over/double charge ( its a machine - it happens )

2)  a bad case were as the capacity was reduced considerably ( would greatly increase pressures )

3) a high primer that caused the round to fire before the bolt was fully engaged ( much like a slam-fire )

stimpy

[Tuckerp229]

"That is a definate "maybe". Try it for your self with no bullets of coarse..  ;DSee if you can get it to fire with out the bolt completely closed..."



I just tried my other  .30 Carbine and was surprised to discover it WILL fire before the rotary bolt is closed and locked!

Tuckerp229

Glad your ok , could have been much worse . Sounds like one of three things happened here .

1)  a over/double charge ( its a machine - it happens )

2)  a bad case were as the capacity was reduced considerably ( would greatly increase pressures )

3) a high primer that caused the round to fire before the bolt was fully engaged ( much like a slam-fire )

stimpy

1. I was immediately prepared to believe I double/overcharged. Yet some things seem to point else where.
2. This I mat never know because the case is now empty and bottomless.
3. This is also possible and related to cwlongshot's idea of it having fired before the bolt was closed and/or locked.

[stimpylu32]

Tuckerp229

I would lean more to the 2nd one , Graybeard himself toaster a 44 mag barrel on a TC in kinda the same way , the powder charge just didn't look right with the others but he loaded and shot it anyhow . 

Not sure how the powder alarm reads on the Dillon , but if it saw the proper amount of powder it would not alarm even though it was in a case with less than what it should have for capacity .

stimpy

[Tuckerp229]

"Not sure how the powder alarm reads on the Dillon , but if it saw the proper amount of powder it would not alarm even though it was in a case with less than what it should have for capacity ."


The alarm is a simple depth plunger that bottoms out on the gunpowder.  It even packs it a bit.  So with the smaller case capacity theory, assuming the correct charge was thrown, the plunger wouldn't have been able to reach the correct depth and the alarm would've sounded.

[csi-cop]

How many times was the brass reloaded and were the primer pockets reamed for depth during it's life. From the description of the brass remains and not seeing it my first thoughts are case head separation or primer pocket blow out. The key from just the description is the loss of wood on the right hand side of the action lending it's self to case head separation. A out of battery firing may cause the same effect but from the two I have seen the case head was still attached to a portion of the case with the split being down the side of the case. As stated in the earlier post it may remain a mystery but check the rear of the bolt and bolt action lug closely under a good magnifying glass for hair line cracking. After a action explosion I would want a older military armorer to check it out and test fire it before placing it back into service.
Walt H

[Bill In SC]

Memories of a long time ago...

Many years ago, I had the same thing happen.  The 30 M1 Carbine will fire out of battery!

ONLY TRY THIS WITH A UNLOADED FIREARM!  Carbine owners can prove this by pulling the bolt fully to the rear, and then ride the bolt forward.  Just before the bolt rotates into the locked battery position, pull the trigger.  Click!!!  It will fire out of battery.

I remember the day well.  Shooting 110 JHP's.  On the 3rd or 4th shot, BOOM....  I was glad I was wearing glasses.  Complete case seperation with most of the case stuck in the chamber.

Something to think about when shooting the old war dog.

[Tuckerp229]

Memories of a long time ago...

Many years ago, I had the same thing happen.  The 30 M1 Carbine will fire out of battery!

ONLY TRY THIS WITH A UNLOADED FIREARM!  Carbine owners can prove this by pulling the bolt fully to the rear, and then ride the bolt forward.  Just before the bolt rotates into the locked battery position, pull the trigger.  Click!!!  It will fire out of battery.

I remember the day well.  Shooting 110 JHP's.  On the 3rd or 4th shot, BOOM....  I was glad I was wearing glasses.  Complete case separation with most of the case stuck in the chamber.

I have become convinced that this is what happened.  I removed the exploded round last night.  There was no metal damage to the gun. Only the stock lost three large flat shards.


Bill in SC, What did you do with your carbine?  Did you have it checked/ repaired, (if there is a repair), by a gunsmith or did you just lube it?

I thank all of you for helping me with your experience.  I might have went on believing that it was a reload issue and not checked the rotary bolt for operation.  The next may have caused injury.   

[Bill In SC]

I still have the Carbine.  Still shoots good with 110 grain SP's.

As to the fix...  I don't think there is one.  I have picked up and checked over a dozen other issue carbines, and they all do it.  I think it's just the nature of the beast.

What I do know is to inspect all 30 carbine ammo to make sure there are no burrs or anything that would possibly hang it up during chambering.  I do keep the bolt well lubed.

I have never had any more problems out of it, but I always keep that day in the back of my mind when I'm out playing with it.  Always have eye protection on, just in case!

[Tuckerp229]

As for lube, I use it sparingly.  However the variable here is that the Minnesota temperature that day was perhaps 4 degrees.  I'm leaning toward partial freeze stiction....just enough to slow the bolt down and cause the rotatry lock to partially engage.  Surely the WWII boys in Bastone had colder sustained weather. I don't know what they used for lube back than but I assume it worked.

[John Traveler]

I've had a couple of M1 Carbine mishaps as you described.

They were traced to excessively short cases (too much case trimming) giving an excessive headspace condition in which the forward part of the cass stuck in the chamber, and the head of the case blew off, ruining the stock and magazine.

I showed the case remmant to the Navy armorer, and the first thing he asked was did I reload the ammunition, and I stated yes, and did I trim the cases, and yes again.  He stated correctly, that the M1 Carbine case capacity was too small to double charge with 2400 or H110 and the 110 grain bullet.  Following his advice, I borrowed a caliper and measured all my reloaded rounds, and found several that were upwards of 0.025" too short!  Lesson learned rather cheaply.

[Steve P]

My guess would be brass too long to allow the bolt to fully close and lock OR the brass too short allowing excessive head space.  Carbine is the ficklest of shooters.  Ammo has to be just right. 

One other thought.....slightly dirty chamber and too light a load to work the action.  Bolt recoiled enough to pick up the next load and chamber it, but did not have enough bolt recoil to completely close the bolt.

Check case length and do a little cleaning.  Hopefully someone's hints have resolved problem so not future issues.

Steve

[Tuckerp229]

Since this was my first reloading of these once fired rounds and since I don't own a trmmer yet, if the case was the issue it must've been a "too long" issue. The sticky bolt, or dirty barrel could've possibly been a factor.
I just ordered an RCBS trim mate with all the case prep' toys.  My next batch will be well within spec', then we'll try it again.

[fastbike]

Universal M1 Carbines are notorious for being able to fire out of battery. I thought the issue did not extend to the service carbines, but it seems like this may be the case.

[Hank08]

Tucker, When shooting reloads in a .30 Carbine this isn't unusual.  With factory ammo it would be very unusual.  All it takes is a case that was fired in a larger chamber and then didn't get resized all the way to the groove so it didn't quite go all the way into the chamber and the bolt was still unlocked when it fired.  I've seen a number of them over the last 40 yrs. It could also happen from a really dirty chamber but usually it's just a fat case that causes it.
H08